--- gforth/extend.fs	1995/11/07 18:06:39	1.12
+++ gforth/extend.fs	1996/02/09 17:34:09	1.15
@@ -37,6 +37,9 @@ decimal
 : 2Literal ( compilation w1 w2 -- ; run-time  -- w1 w2 ) \ double two-literal
     swap postpone Literal  postpone Literal ; immediate restrict
 
+: dabs ( d1 -- d2 ) \ double
+    dup 0< IF dnegate THEN ;
+
 : m*/ ( d1 n2 u3 -- dqout ) \ double m-star-slash
     >r s>d >r abs -rot
     s>d r> xor r> swap >r >r dabs rot tuck um* 2swap um*
@@ -129,25 +132,59 @@ decimal
 \ SOURCE-ID SAVE-INPUT RESTORE-INPUT                    11jun93jaw
 
 : source-id ( -- 0 | -1 | fileid ) \ core-ext source-i-d
-  loadfile @ dup 0= IF  drop loadline @ 0 min  THEN ;
+  loadfile @ dup 0= IF  drop sourceline# 0 min  THEN ;
 
 : save-input ( -- x1 .. xn n ) \ core-ext
-  >in @
-  loadfile @ ?dup
-  IF    dup file-position throw loadline @ >tib @ 6
-        #tib @ >tib +!
-  ELSE  loadline @ blk @ linestart @ >tib @ 5 THEN
-;
+    >in @
+    loadfile @
+    if
+	loadfile @ file-position throw
+    else
+	blk @
+	linestart @
+    then
+    sourceline#
+    >tib @
+    source-id
+    6 ;
 
 : restore-input ( x1 .. xn n -- flag ) \ core-ext
-  swap >tib !
-  6 = IF   loadline ! rot dup loadfile !
-           reposition-file IF drop true EXIT THEN
-      ELSE linestart ! blk !
-           dup loadline @ <> IF 2drop true EXIT THEN
-           loadline !
-      THEN
-  >in ! false ;
+    6 <> -12 and throw
+    source-id <> -12 and throw
+    >tib !
+    >r ( line# )
+    loadfile @ 0<>
+    if
+	loadfile @ reposition-file throw
+    else
+	linestart !
+	blk !
+	sourceline# r@ <> blk @ 0= and loadfile @ 0= and
+	if
+	    drop rdrop true EXIT
+	then
+    then
+    r> loadline !
+    >in !
+    false ;
+
+\ : save-input ( -- x1 .. xn n ) \ core-ext
+\   >in @
+\   loadfile @ ?dup
+\   IF    dup file-position throw sourceline# >tib @ 6
+\         #tib @ >tib +!
+\   ELSE  sourceline# blk @ linestart @ >tib @ 5 THEN
+\ ;
+
+\ : restore-input ( x1 .. xn n -- flag ) \ core-ext
+\   swap >tib !
+\   6 = IF   loadline ! rot dup loadfile !
+\            reposition-file IF drop true EXIT THEN
+\       ELSE linestart ! blk !
+\            dup sourceline# <> IF 2drop true EXIT THEN
+\            loadline !
+\       THEN
+\   >in ! false ;